New information has emerged:

[More Dual Shock 3 Details Emerge 9/22/07
Unless you've been living under a rock on Mars, you've already heard about the Dual Shock 3, recently confirmed during Sony's keynote address at the Tokyo Game Show. And when it was unveiled, most noted a couple things; one of which was an important question: 1. it doesn't seem to change the cosmetic appearance of the Sixaxis, and 2. is the new rumble functionality any different than what we had in the Dual Shock 2?

Well, it appears the answer to that remains a bit up in the air, but the consensus seems to be that the rumble feature in DS3 does indeed feature new technology. Initially, one Sony source said the Dual Shock 3 will be identical to the Dual Shock 2- According to the Advanced Media Network, Sony's Kimberly Otzman said the rumble "will be exactly the same in both controllers with no difference in technology." This doesn't appear to be the case, though, as several sources, including 1Up, have put their hands on the new controller and found the rumble actually comes from different spots. They were playing MGS4 with it, for example, and when getting shot at from a certain direction, the controller would...well, rumble in that general direction. That'd be like our own little personal radar!]
http://www.psxextreme.com/ps3-news/1886.html

[We did enjoy the various rumble effects employed by the new Dual Shock 3 controller, though: As explosions rattled around Snake, we could actually feel the direction from which they were coming based on what part of the controller vibrated.]
http://www.1up.com/do/previewPage?cId=3162991


Exciting! From these statement I'd say there's a strong possibility that Sony is actually using a "same size/dual actuator" TouchSense solution for the SIXAXIS as described in an IMMR patent application (which includes drawings of a DualShock controller). I've edited the patent to make it apply to the PS3 in particular.

[United States Patent Application 20060281550
Schena; Bruce M. December 14, 2006

Directional inertial tactile feedback using rotating masses

[0006] One problem with such existing tactile controllers [DualShock 2] is that they can provide output inertial forces only in the general directions ("swirl") of the rotating mass. The sensations thus feel to the user as if they are not output in any particular direction, but are simply output on the housing of the device. However, many events in games and other computer-implemented environments are direction-based. For example, in a driving game, the user may be driving a vehicle that impacts a side wall, or gets impacted by another vehicle. These events should cause directional forces on the interface device to allow the user a more realistic simulation of the event; thus if the user's car is impacted on the left, a force should be output on the device in the corresponding direction. However, the haptic inertial devices currently available do not allow such directional output of inertial forces.

SUMMARY OF THE INVENTION

[0007] The present invention is directed toward providing directional haptic feedback for a...[SIXAXIS controller].

[0008] More particularly, a [SIXAXIS controller]...outputs directional inertial sensations to a user which can be based on interactions and events occurring in a graphical environment displayed by the [PS3]. The device includes...a plurality of actuators producing inertial forces when the actuators are driven by control signals. Each of the actuators includes a rotatable eccentric mass positioned offset on a rotating shaft of the actuator, where the actuators are rotated simultaneously such that centrifugal forces from the rotation of masses combine to output...a desired direction...

[0009] A phase difference between the eccentric masses of the actuators can determine a direction of the single desired axis...Each actuator can include a sensor that detects a rotational position of the eccentric mass. The desired directional axis of output can be determined by an event or interaction occurring within said graphical environment, such as a collision in a game. A method of the present invention provides a phase difference between eccentric masses and rotates the eccentric masses to provide inertial sensations along a desired direction.]

http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch
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